Ethanol is a member of the alcohol family. Alcohols contain an OH group covalently
bonded onto a carbon chain. Their general formula is CnH2n+1OH.
The boiling points of
The major ore of chromium is chromite, FeCr2O4. Some chromium is extracted directly from
this ore to produce an alloy of iron and chromium and is used to prepare stainless steel.
But if pure chromium is needed, the chromite must first be converte
Use of the fractions
All hydrocarbons burn in air to form carbon dioxide and water. They also release a lot of
heat in the process; therefore they can be used as fuels.
If there isnt enough air or oxygen, you get an incomplete combustion, this leads to th
Hydrocarbons are compounds of carbon and hydrogen only. There are two common
families of hydrocarbons, the alkanes and the alkenes. Members of family have similar
chemical properties and physical properties gradually from one member to anothe
Aluminium metal is always covered in a thin layer of aluminium oxide. This oxide layer can
be made thicker to protect the metal from corrosion. The aluminium object is made the
anode of an electrolytic cell. Oxygen is produced at the
Chemical reactions are accompanied by an energy change, which, in solution, may be
detected as a temperature change.
Exothermic reactions are reactions where heat energy is released and given out to the
surroundings. Endothermic reactions are r
Sulphur is a solid, yellow element. It is found in many places of the
world and is often released by volcanoes. Many elements form
compounds with sulphur. These are called sulphides. Many of the
most important metal ores are sulphides, such as gal
The Transition metals
They are all typical metallic elements. They are good conductors of heat and
electricity, workable, strong and mostly high densities. Apart from mercury,
they all have reasonably high to very high melting points. They are much less
Reaction with sodium
Alcohols react gently with sodium to produce hydrogen. The product is sodium ethoxide
and this reaction is often used to treat small sodium spills or dispose of small amount of
2Na (s) + 2C2H5OH (l) 2C2H5ONa (s) + H2
The chlorination of methane
Halogenation is the replacement of one or more hydrogens in an organic compound by
halogen atoms. This is called a substitution reaction. The reactions use light energy to
start. When methane is reacted with chlorine the produc
Most carbonates split up to give a metal oxide and carbon dioxide when you heat them.
You can test the carbon dioxide given off using limewater and there may be some helpful
colour changes as well.
If you add a dilute acid to a solid carbonate,
3.1 Early History of Atomic Theories
Democritus: matter is made up of tiny indivisible particles called atoms
Dalton: the atom is indivisible, atoms of the same element are identical but different from other
No sub-atomic particles or isotopes